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Environmental and Biosafety issuesin modern Biotechnology
Dr Veena Chhotray, IASSenior Fellow, TERI
6th February, 2006
‘Biosafety’ means the need to protect human and animal health and environment from the possible adverse effects of the products of modern biotechnology
BIOSAFETY
Environmentalism emerged as a distinct development in the last forty years. Emergence of “pressure groups” in the sixties First Earth Day (1970) The United Nations Conference on the Human
Environment and Development (1972) The Brundtland Report: our Common Future
(1987) The Rio Earth Summit (1992) Convention on Biodiversity (CBD) [1992] Cartagena Protocol on Biosafety (CPB) [1993]
International Evolution
Convention of Biodiversity (CBD) [1992] Focus: conservation and sustainable use of
biodiversity Recognized the potential of modern biotechnology
for human well being Took cognizance that modern biotechnology
could have serious effects on environment and health
Article 8(g) emphasized the need to regulate the risks associated with the use of LMOS.
Article 19(3) set the stage for a legally binding international instrument about biosafety.
The Cartagena Protocol on Biosafety (CPB) Entered into force on 29th December 1993 Focus on transboundary movement of the
LMOS. Seeks to lay down an internationally acceptable
framework to provide for an adequate level of protection against the possible adverse affects of LMOS on biodiversity and human health.
Basic Premises of CPB “Advance Informed Agreement” between Parties
(AIA) Decision on the basis of scientific risk
assessment Precautionary Principle
How is Genetic Engineering (GE) different from conventional breeding (CB)? Combining DNA in new combinations and
introducing it into a new organism are the GE tools.
Main differences between CB and GE Ability to move across sexual barriers Amount of change: a specific gene embodying a
particular trait or thousands of genes embodying desirable and undesirable traits
Occurrence of change in one or several generations.
Two diametrically opposite trends of thought US-Canada
No new risks associated with GM crops New regulations not considered necessary Safety assessments
‘Product’ rather than ‘process’ based In comparison and contrast to their ‘familiarity’ and
‘substantial’ equivalence to conventional crops
Is GE inherently unsafe?
EU GE crops considered new and special Existing legislation not considered sufficient
Safety assessment Process based Principle of ‘substantial equivalence’ beginning rather than
the end
Adoption of ‘Precautionary Principle’ as guide
…Is GE inherently unsafe?
GE technology carries certain inherent unpredictability Some facts
Isolation of a gene from its natural environment and integration into entirely different organism
Possible transgenic instability due to triggering of the inbuilt defense mechanisms of the host organism leading to inactivation or silencing of foreign genes.
….Is GE inherently unsafe?
Possibilities of integration of foreign gene at a site predisposed to silencing of genes (position effect). Variance in the levels of expression of the
transgene in different environmental conditions (heat, humidity, light…..)
Possibilities of silencing of genes arising in subsequent generations
….Is GE inherently unsafe?
Case by case sound scientific
assessment is of utmost significance
Relate to environmental, human and animal health consequences
Both can have short and long term implications Biosafety risks involve the entire spectrum of biodiversity A universal ‘true for all’ approach may not be applicable
Biosafety issues in transgenic crops
Known Probability Unknown Probability
Risks
•Rigorous Scientific Assessment•Risk Mitigation
•Precautionary Principle
Biosafety concerns arise from:
Horizontal gene transfer Genetic contamination Transfer of allergens and toxins from one
life form to another and creation of new toxins and allergenic compounds
..Biosafety issues in transgenic crops
-
Main ConcernsDevelopment of aggressive weeds/ wild relatives by
transfer of transgenic traitsErosion of land races/wild relatives by genetic
pollution in centres of origin/ diversityHarm to the non-target organismsDevelopment of pest resistance by prolonged useMonoculture and limitations to farmers’ choice in
crop managementHazard to human and animal health by transfer of
toxins and allergens and by creation of new toxins and allergenic compounds
..Biosafety issues in transgenic crops
-
Assessment GE venturing into an unknown biological
territory ASILOMAR Conference (1975): No research till
safety guidelines in place Initially, focus on laboratory safety procedures Wider definition of biosafety with possibilities of
commercialization of GM products The broad format of biosafety parametres
essentially the same in all regulations
..Biosafety issues in transgenic crops
Two main stages:
1. Laboratory/green house stage
2. Confined Trial Stage
IMPORTANTPrevention of the spread of genetically
engineered material outside lab/field
..Biosafety issues in transgenic crops
Laboratory/green house stage
Different biosafety levels as per the degree of risk involvedTwo methods of containment
PhysicalBiological
A confined trial is a small scale release of a transgenic plant species for research purposes conducted under conditions that prevent spread of the organism and mitigate its impact on the surrounding environment
Objective is to collect data to evaluate the crops’ performance
Confined Trial Stage
Risk mitigation – the terms and conditions that are necessary to conduct the trial safely.
Prevent Gene Flow Prevent entry of GMOs into food chain Prevent Persistence of GMOs in the field
Focus on Risk Mitigation
Bio-pharmaceutical therapeutics
Biosafety risk Survival, multiplication and dissemination of
GMOs in contained/ open environment Interaction of GMOs with biological systems Routes of dissemination: physical; biological
Risk depends upon Nature of organism invovled Extent of use of LMOs End product LMO or not?
…Bio-pharmaceutical therapeuticsRisk categorization of micro organisms: determining factors Capability to cause disease Hazard to laboratory workers Risk of spread to community Availability of effective treatment
Health risks Toxigenicity Pathogenicity Allergenicity Antibiotic resistance
..Bio-pharmaceutical therapeuticsEnvironmental risks Outcrossing between GMOs and pathogens Negative effects on populations of non target
organismsRisk assessment Access Expression DamageRisk management and communication Physical Biological
Expressed proteins generally not a part of regular food supply
Food complex mixtures e.g. nutrients, anti-nutrients and natural toxins
Directly enter human system Assume different forms Involve storage, processing, transportation
GM foods: need for safety assessment
Guidelines by Codex Alimentarius Commission Assessment of possible allergenicity Assessment of possible toxicity Compositional analysis of key components Food processing Nutritional modification
.. Safety assessment of GM foods comprise
….GM foods: Allergenicity; ToxicityAllergy
It is a hypersensitive reaction initiated by immunologic mechanisms caused by specific substances called allergens. Assessment Is the gene source allergenic?Expression level of introduced geneUnintended effectDigestibility and heat stability
Toxicity New proteins as a result of intended modification Unintended new proteins as a result of the modification Natural constituents beyond their level of normal
variation
….GM foods: nutritional aspects; unintended effects
Intended and unintended changes in nutrient levels Bioavailability of nutrients, stability and processing Presence and effect of anti-nutrients Impact of individual changes on overall nutritional profile Unintended effectsRandom integration of transgenes Insertional mutagenesis Disruption of gene functions Production of new proteins Changes in
o Phenotype Metaboliteso Enzymes Toxinso Genotype
Concluding Note……
Biosafety is integral to modern biotechnology The adoption of modern biotech products
needs to be balanced with adequate biosafety safeguards
Case by case scientific risk assessment and cost benefit analysis
Greater acceptance of health care applications Need based adoption in GM crops and foods Participation of various stakeholders Dissemination of knowledge and information